The Iro is not an internet appliance. You can't 'talk' (connect) to it directly. It will have a local IP address, but, there's no internet server internal to the Iro to 'communicate' with.
If you were making a list of pluses and minuses of the Iro as compared to competing controllers this (not an internet appliance) would go on the minus side. It won't work without a WiFi connection. And the product immediately becomes useless if Rachio goes out of business.
On the plus side would be (probably substantial) lower cost (not trying to do as much locally, less R&D) and greater capability (all the 'heavy lifting' (algorithms, tracking per zone) can easily be done in the cloud). Internet appliance or not is many times a market and investment driven (irreversible) decision.
As another example my WiFi thermostats are internet appliances. They each have a local IP address that I can 'talk' to without having a WAN connection. I won't get some things like outside temp or forecast, or be able to adjust them remotely, but, they'll control the A/C or furnace just fine during any periods of lost internet connectivity.
As a further example my WiFi hot water heaters are not internet applieances. They work just like the Iro does. I change the hot water temp on my smart phone, the change goes to the cloud, and down from the cloud is the changed temperature. Very simple, and at not much cost.